The present invention relates to a hand-held microscope and in particular to one in which articulated members are movable towards and away from each other to focus same.
Hand-held microscopes are known in the prior art. Slide viewers with fixed focuses and which are hand-held are disclosed in U.S. Pat. Nos. 2,986,830, 3,734,596 and 3,756,699. These viewers have the disadvantage of not permitting focusing on the object being viewed and thus would be disadvantageous for use as a hand-held microscope.
Hand-held microscopes of complex construction are known from U.S. Pat. Nos. 251,721 and 2,635,504, Australian Pat. No. 131,216, German Pat. No. 898,085 and British Pat. No. 820,215. In these constructions, focusing is achieved by rotating a screw and nut assembly which effects relative movement of the lens of the microscope with respect to the object being viewed. These devices have the disadvantage of not permitting quick focusing adjustment as is generally needed when the user wants to view a large number of slides one after the other.
A quicker focusing mechanism is illustrated in U.S. Pat. Nos. 1,669,870, 3,391,975 and 4,095,874. The reading machine shown in U.S. Pat. No. 1,669,870 is sufficient for reading books or other printed materials, however the construction does not lend itself to the observing of slides and other like materials. In U.S. Pat. Nos. 3,391,975 and 4,095,874, while these are simple hand-held microscopes, they require the user to utilize both hands for focusing and observing a slide. Moreover, neither microscope is capable of adjusting the lens power thereof to be useful in a variety of applications.